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      <a id="ntrpol"></a>
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        <h2>
          <span class="refentrytitle">ntrpol</span>
        </h2>
        <p>ntrpol — 
      Calculates the weighted mean value of two input signals.
          </p>
      </div>
      <div class="refsect1">
        <a id="idp128026768"></a>
        <h2>Description</h2>
        <p>
      Calculates the weighted mean value (i.e. linear interpolation) of two input signals
    </p>
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      <div class="refsect1">
        <a id="idp128028064"></a>
        <h2>Syntax</h2>
        <pre class="synopsis">ares <span class="command"><strong>ntrpol</strong></span> asig1, asig2, kpoint [, imin] [, imax]</pre>
        <pre class="synopsis">ires <span class="command"><strong>ntrpol</strong></span> isig1, isig2, ipoint [, imin] [, imax]</pre>
        <pre class="synopsis">kres <span class="command"><strong>ntrpol</strong></span> ksig1, ksig2, kpoint [, imin] [, imax]</pre>
      </div>
      <div class="refsect1">
        <a id="idp128090000"></a>
        <h2>Initialization</h2>
        <p>
      <span class="emphasis"><em>imin</em></span> -- minimum xpoint value (optional, default 0)
    </p>
        <p>
      <span class="emphasis"><em>imax</em></span> -- maximum xpoint value (optional, default 1)
    </p>
      </div>
      <div class="refsect1">
        <a id="idp128092528"></a>
        <h2>Performance</h2>
        <p>
      <span class="emphasis"><em>xsig1</em></span>, <span class="emphasis"><em>xsig2</em></span> -- input signals
    </p>
        <p>
      <span class="emphasis"><em>xpoint</em></span> -- interpolation point between the two values
    </p>
        <p>
      <span class="emphasis"><em>ntrpol</em></span> opcode outputs the linear interpolation between two input values. <span class="emphasis"><em>xpoint</em></span> is the distance of evaluation point from the first value. With the default values of <span class="emphasis"><em>imin</em></span> and <span class="emphasis"><em>imax</em></span>, (0 and 1) a zero value indicates no distance from the first value and the maximum distance from the second one. With a 0.5 value, <span class="emphasis"><em>ntrpol</em></span> will output the mean value of the two inputs, indicating the exact half point between <span class="emphasis"><em>xsig1</em></span> and <span class="emphasis"><em>xsig2</em></span>. A 1 value indicates the maximum distance from the first value and no distance from the second one. The range of <span class="emphasis"><em>xpoint</em></span> can be also defined with <span class="emphasis"><em>imin</em></span> and <span class="emphasis"><em>imax</em></span> to make its management easier.
    </p>
        <p>
      These opcodes are useful for crossfading two signals.
    </p>
      </div>
      <div class="refsect1">
        <a id="idp128101104"></a>
        <h2>Examples</h2>
        <p>
      Here is an example of the ntrpol opcode. It uses the file <a class="ulink" href="examples/ntrpol.csd" target="_top"><em class="citetitle">ntrpol.csd</em></a>.
      </p>
        <div class="example">
          <a id="idp128102960"></a>
          <p class="title">
            <strong>Example 550. Example of the ntrpol opcode.</strong>
          </p>
          <div class="example-contents">
            <p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p>
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>
<span class="comment">; Select audio/midi flags here according to platform</span>
-odac    <span class="comment">;;;realtime audio out</span>
<span class="comment">;-iadc    ;;;uncomment -iadc if real audio input is needed too</span>
<span class="comment">; For Non-realtime ouput leave only the line below:</span>
<span class="comment">; -o ntrpol.wav -W ;;; for file output any platform</span>
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>

<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">ksmps</span> <span class="op">=</span> 32
<span class="ohdr">nchnls</span> <span class="op">=</span> 2
<span class="ohdr">0dbfs</span>  <span class="op">=</span> 1

giSin <span class="ohdr">ftgen</span> 1, 0, 1024, 10, 1

<span class="oblock">instr</span> 1

avco <span class="opc">vco2</span>   .5, 110			<span class="comment">;sawtootyh wave</span>
asin <span class="opc">poscil</span> .5, 220, giSin		<span class="comment">;sine wave but octave higher</span>
kx   <span class="opc">linseg</span> 0, p3<span class="op">*</span>.4, 1, p3<span class="op">*</span>.6, 1	<span class="comment">;crossfade between saw and sine</span>
asig <span class="opc">ntrpol</span> avco, asin, kx
     <span class="opc">outs</span>   asig, asig

<span class="oblock">endin</span>
<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>

<span class="stamnt">i</span> 1 0 5
<span class="stamnt">e</span>
<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
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        <p><br class="example-break" />
    </p>
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      <div class="refsect1">
        <a id="idp128107248"></a>
        <h2>Credits</h2>
        <p>
      </p>
        <table border="0" summary="Simple list" class="simplelist">
          <tr>
            <td>Author: Gabriel Maldonado</td>
          </tr>
          <tr>
            <td>Italy</td>
          </tr>
          <tr>
            <td>October 1998</td>
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        <p>
    </p>
        <p>New in Csound version 3.49</p>
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